The hard state of X-ray binaries (XRBs) is associated with a
hard power law spectrum in the X-ray band, generally modeled
via inverse Comptonization of thermal disk photons by a
corona. This state is also associated with compact,
continuous jets whose radio synchrotron emission is
correlated with the hard X-rays. The exact nature of this
relationship is still under debate, and an effective way of
addressing this question is to model the entire broadband
spectrum self-consistently. Depending on the location of the
optically thick-to-thin break and the emitting particle
distribution, jet synchrotron radiation can contribute
significantly to the X-ray band, in addition to synchrotron
self-Compton emission from near the base of the jets. We
have imported our jet models into X-ray data analysis
software to allow the simultaneous fitting of radio and IR
data along with the traditional X-ray bands. We present the
fits to broadband simultaneous data sets, including X-ray
data from the Rossi XTE mission, for several XRBs,
including Cyg X-1 and GX 339-4. Our best results show
contributions from both direct synchrotron radiation as well
as a strong SSC component. With the addition of line and
reflection features, jet models provide as good a
description of the X-ray data as thermal Comptonization
models, while also addressing the radio/IR components.
S.M. is supported by an NSF Astronomy & Astrophysics
postdoctoral fellowship.

The author(s) of this abstract have provided an email address
for comments about the abstract:
sera@space.mit.edu